How to detect transport start/stop?

Noob question. How do I detect transport start/stop (that is, how can I get a message or "bang" when the live transport starts, and another message or "bang" on another output when the transport stops?

I have been using the transport object, together with a free running metro object to detect stop, but that feels a lot like a workaround, and doesn’t work properly if I want to detect the exact moment the transport starts (for resetting stuff after stop, it’s good enough)